Excavating machine



Aug. 4, 1936. R. E. LJUNGKULL EXCAVAT ING MACHINE l Filed April 25, 1934 8 Sheets-Sheet l Invenbor. Rolf ELJungkull. BJ?.

Aug. 4, 1936. RE. LJUNGKULL EXCAVATING MACHINE 8 Sheets-Sheet 2 i Filed April 25, 1954 Inv@ ntor.' Rolf E. LJ'ungkull.

Aug. 4, 1936.

R. E. LJUNGKULL EXGAVATING MACHINE Filed April 23, 1934 8 Sheets-Sheet 5 @L a |IJ1) vm .uw Ow @/Nn. am r. n! vo. ma. n... om 0 I nv@ nto r;

Rolf Eljungkull.

)Wig f /ff-H'or-ne A g- 4, 1936- R. E. L JUNGKULL 2,049,653

EXCAVAT ING MACHIN Filed April 23, 1934' 8 Sheets-Sheet 4 \439 Inventor:

' g'Rolf E. Ljungkull.

Aug. 4, 1936.

R. E. LJUNGKULL EXCAVATING MACHINE Filed April '25, 1954 8 sheetssheet 5 |38/ T g |454 o Fig. 13 |43 m6 mi M80 4 l lV1 r11/49 73' 181 so 3S "1s Inventor: 36 L )ungkull torney.

Aug. 4, 1936. R. LJUNGKULL EXCAVATING MACHINE 1934 8 Sheets-Sheet 6 Filed April 23 A I'ventor: Rolf .ELJungkulL BH/QR@ Aug. 4, 1936,

R. E. LJUNGKULL EXCAVATING MACHINE Filed April 23, 1934v 8 Sheets-Sheet '7 Hmv/NQ Aug. 4, 1936. R. E. L JUNGKULL EXCAVATING MACHINE Filed April 23, 1954 s sheets-Sheet 8 .27% ffft'torneg.

vPatented Aug. 4, 1936 PATENT OFFICE sXcAvA'rrNc MACHINE een n. murieron, st. ram, Mann., assigner to American ll-lloist and Derrick Company, St. Paul, Minn., a corporation of Delaware Application April 23, 1934, Serial No. 721,983

l0 Claims.

This invention relates to an excavating machine, and the genera-l object of the-invention is to provide an excavating machine wherein will be incorporated various improved features and characteristics of construction novel both as inn dividual entities of the machine and in combination with each other.V

A further object is to provide an excavating machine which will include a bull gear, as well as a bull gear arrangement, of novel and improved construction.

A further object is to provide an excavating machine which will include a car body and a bull gear associated therewith in novel and improved manner. y

A further object is to provide an excavating machine which will include a car body of novel and improved construction.

A further object is to provide an excavating` machine comprising a car body, a revolvable platform upon said car body and supportingva mast structure, boom, bucket or dipper, operating mechanism, etc., and a novel and improved association of said platform with said car body, whereby the platform can be easily and conveniently revolved upon an axis for said platform carried by the car body.

A further object is to provide ari-excavating machine the platform of which will support an upper rail or rails riding rollers or wheels of a container ring of the excavating machine, which rollers or wheels in turn ride the operative rail of the bull gear of the machine, theV whole constituting a novel and improved construction in excavating machines.

A further object is to provide in the excavating machine, a novel and impro-ved construction of mechanism for revolving the platform about its axis upon the car body.

A further object is to provide an excavating machine which will include a platform, desirably having walkways thereon, of novel and improved` construction. f

A further object is to provide an excavating machine vwhich will include a container ring with rollers or wheels constituting novel and improved mounting for the mast upon the platform of the machine.

A further object is'to vprovide an excavating machine which will include a novel and improved back brace mounted upon the 'platform of the 5 machine in new and improved manner.

A further object is to provide in the excavating machine, a mast and a back brace mounted upon the platform of the machine, and means of novel and improved construction connecting upper portionsl of said mast and back brace with each other. Y

With the above objects in view, as well as others which will appear as the specification proceeds, the invention comprises the construction, y arrangement and combination of parts as now to be fully described and as hereinafter to be specifically claimed, it being understood that the disclosure herein is merely illustrative and intended in no way in a limiting sense, changes in details of construction and arrangement of parts being permissible so long as within the spirit of the invention and the scope of the claims which follow. Y

In the accompanying drawings forming a part of this specification,-

Fig. 1 is a side elevational view of an excavatingy machine in which the features of the invention are incorporated, parts being omitted and broken away;

Fig. 2 is a top plan View of the machine, parts being omitted;

Fig. 3 is an enlarged elevational view of the platform of the machine, as seen from the left in Fig. 2;

Fig. 4 is a vertical, longitudinal sectional view of the machine, parts being omitted and broken away;

Fig. 5 is an enlarged horizontal sectional view, taken as on line 5-5 in Fig.v4, detailing features of the platform and the revolving mechanism therefor, as welll as features of the mounting for the platform upon the car body;

Fig.` 6 'is' an enlarged horizontal Sectional View, taken as on line 6--6 in Fig-4, detailing features of the bull gear and of the vcar body of the machine;

l Fig. 7 is an enlarged vertical sectional view, taken as on line ,1-1 in Fig. 6, detailing additional features of the bull gear and the car body; 50`

Fig. 8 is a reducedv horizontal sectional View, taken as online 8-8 in Fig. 7, detailing features of the car body;

Fig. 9 is'an enlarged vertical .sectional View taken ason line 9 9 in Fig..4, detailing features 55 of the container ring of the machine and showing one of the duplicate platform supporting rollers or wheels carried by said container ring;

Fig. 10 is an enlarged vertical, transverse sectional view, taken as on line IIJ-I6 in Fig. 6, detailing still additional features of the car body;

Fig. 11 is a fragmentary plan view of the car body;

Fig. 12 is anenlarged vertical sectional view, taken as on line |2|2 in Fig. 6, further detailing features of the car body;

Fig. 13 is an enlarged vertical sectional View, taken on line |3|3 in Fig. 2, detailing features of the mechanism for revolving the platform upon the car body;

Fig. 14 is a side elevational view showing a continuation of the boom of Fig. 1, parts being broken away;

Fig. 15 is an enlarged fragmentary siderelevational view detailing features of the boom;

- Fig.l 16 is a detail sectional View of the boom,

in Fig. 1, disclosing a lower fragment'ofthe boom` in top plan as when swung toward horizontal position in said Fig. 1;

Fig. 20 is a top plan View of the upper or outer portion of the boom of Fig. away;

Fig. 21 is a'detail sectional View of the boom, taken on line 2|--2| in Fig. 19;

Fig. 22 is a detail sectional View of the mounting4 for the boom, taken on line 22-22 in Fig. 1;

Fig. 23 isa detail sectional View, taken on line 23-23 in Fig. 1, disclosing the back brace of the excavating machine in top elevation;

Fig. 24 is a sectional View detailing features of the mounting for the back brace upon the platform, taken on line 24-24in Fig. 1;

Fig. 25 is a sectional View detailing features of the lower portion of. the connection between the back brace and the mast, taken on line 25-25 in Fig. 1; l

Fig. 26 is a detail sectional View, taken on line 26-'26 in Fig. 1, disclosing thev mast intop elevation;

Fig. 27 is asectional view detailing features of the upper portion of the connection between the back brace and the mast, taken on line 21-21 in Fig. 1;

19, parts being broken Fig. 28 is a detail perspective .view disclosing a slotted end portion of an I-beam of the platform for receiving plates upon which the boom and mast are mounted; and- Fig. 29 is a sectional view detailing features of the mounting for the mast upon the platform, taken o-n line 29-29 in Fig. 1.

With respect to the drawings and the numerals of reference thereon, theexcavating machine includes a car body or frame 3| having bearings for axles 32 which rigidly support traveling wheels 33. The machine may be self, or otherwise, propelled along the jtrack 34. l

The car body or frame 3| vis of the novel and improvedjconstruction very clearly disclosedV in Figs. 1, 1, 6,7, 8, 1o, 11, 12 and 13. As there shown, said cai` bodyor frame includes longitudinally extending frame members 35 at thesides of the carbody, and transversely extending frame members 36 at the ends of said car body. Each side frame member 35 consists of. a pair of elongated and lower anges, denoted 46 and 4|, respectively, of said I-beams welded together, as shown Very clearly at 42 in Figs. 6, '7, 8 and 10. Portions of the meeting edges of the upper anges 40 and lower flanges 4| are cut away, and metal 43 to weld said flanges together is placed in said cut-away portions in' any well known manner. Also at spaced apart intervals along the lengths of the side frame members 35, the connected I- bearns are desirably reinforced by transverse webs 44 welded to the body portions or webs 39 and to the flanges of said I-beams, as well as by U-bars 45 and ller bars 46 between adjacent body portions or webs 39, the U-bars and filler bars beingshown as riveted to the body portions or webs. The transverse webs 34, U-bars 45 and filler bars 46 could be attached to the I-beams in a manner different from that shown. Each end frame member 36 consists of an I-beam extending between the side frame members 35, there being an end frame-member 36 adjacent each end of the car body in spaced relation to the outermost extremities of said side frame members 35. The end frame members 36 are perpendicular to the side frame members 35. As disclosed more clearly in Figs. 4, 6, 10, 1l and 13, the innermost upper and lower ilang-es, denoted 41 and 48, respectively, of the side frame members 35 detachably support, as by screw bolts 49, plates 53 at the inner sides of the upper and lower flanges, denoted 5| and 52, respectively, of. the opposite end portions of each end frame'member 36, and said plates 56 are welded to said upper and lower flanges 5| and 52, as at 53'. The end frame members or I-beams 36 are desirably reinforced by transverse webs 54. VSaid end frame members or I-beams 36 are themselves interconnected by spaced apart I-beams, denoted 55 and 56, respectively, extending lengthwise of the car body at opposite sides of the longitudinal center thereof. Opposite end portions of flanges of said I-beams 55 and 56 are detachably connected, as by bolts 5l, to adjacent flanges of the end frame members or I-beams 36, the anges of. said I-beams 55 and 56 lying between the flanges of said I-beams36. Also, each I-beam 55 and 56 includes transverse webs 58 at the opposite ends thereof, which webs are bolted, as at 59 in Figs. 6 and l0, to the body portions or webs of the I-beams 36. As shown in Figs; 6, l0 and 11, a plat'e 66 is interposed between an upper flange of each I-beam 36 and the flanges upon the adjacent ends of the I-beams 55 and 56, and said I-beams 55 and 56 are bolted as at 51 to said plates 60 as well as to the I-beams 36. A pair of reinforcing plates, denoted 6| and 62, respectively, extend transversely of the car body at the opposite sides of the transverse center thereof, said plates 6| and 62 lying between the bodies or webs of the I-beams 55 and 56 and being welded or otherwise fastened to said I- beams 55 and 56. As shown more clearly in Figs. 6 and 12, four plates, each denoted 53, are bolted, as at 64, to the upper, outer flanges of the I-beams 55 and 56, said plates 63 being equally spaced from the vertical axis of the car body and at equal distances apart. to a channel member 65, as at 66, and each of the four channel members 65 extends horizontally outwardly toward a corner of the car body. A relatively short I-beam 61 adjacent each corner Each plate 63 is welded 70 ofthe car body extends obliquely to the side and end frame members vand 36 desirably at a fortyve degree angle to each frame member. The I.beams 6l may include reinforcing webs 68. 1 An end portion of each I-beam 6l is suitably welded to an end frame member or vI-beam 36 as at 69, and the upper and lower flanges of the opposite end portion of each I-beam 5l are welded to the upper and lo-w-er plates 55, as at l5. The body portion or web of each I-beam 5l is welded as at 'H to a vertical plate l2 which is detachably bolted, as at i3, to the body portion'or web of the inner li-beam of each side frame member. Obviously, there are four vertical plates l2. In addition, there are four vertical plates 'ill bolted as at l5 to the body portion or web of the inner I-beam of. each side frame member to which the opposite end portions of each end frame member or I-beam 35 are welded as at i6. The outer ends of the channel members t5 are bolted as at 88 to plates 89 welded to the I-bea-ms 5l..

The axles 32 for the car wheels are mounted in the body Vportions or webs of the I-beams of the side frame members, as will be apparent, and the lower flanges of said I-beams of the side frame members are cut away, as denoted at 'll in Fig. 6, to accommodate the car wheels.

An important feature of, the invention is a novel and improved bull gear associated with the car body or frame of the excavating machine in new and improved manner. The construction of the bull gear and its assembly .with the car body Vor frame will be clear by reference to Figs. 1, 4, 6, 7,V lil and 13. As there disclosed, said bull gear consists of an inner annular portion i8 providing an internal, vertically disposed gear surface or toothed portion i9, an outer annular-upstanding or vertical portion dll providing an operating rail 8l of the bull gear constituting the lower rail of the excavating machine, and an annular hori- Zontal portion or web t2 integrally connecting the lower parts of the portions lil and til. The bottom surface of the horizontal portion or web 82 is at. As disclosed, the b-ull `gear consists of two equal halves each extending 180, and said halves of the bull vgear are detachably connected to each other by bolts 83 arranged in reinforcing anges or webs 8f3 upon the different halves of said bull gear at the meeting ends of the two halves. The bull gear includes additional reinforcing flanges or webs 3ft at spaced intervals about its periphery. In practice, the bull gear can if desired be cast as a continuous circumferential member. Preferably, however, it is when so cast cut to provide twodiametrical halves detachably connected in the manner as illustrated and described.

As disclosed, the bull gear is placed upon the car body or frame so that the end portions of the detachably connected halves thereof lie directly over the midlengths of the side frame members 35. When said bull gear is upon the car body or frame, the circumference of the horizontal portion or web 3?; rests upon the upper flanges of the I-beams 3S and as well as upon the upper flanges of the I-beams 3l and 38; that is, upon the side frame members 35. The bull gear is desirably welded, as at 85, to the upper anges `of the I-beams 3S, and is welded, as at 86,'to the upper flanges of the I-beams 51. Also, the bull gear is desirably detachably bolted, as at 81, to the side frame members and end frame members 35 and 35. lt will be evident from the drawings and from the description above ap-y pearing that the assembly including the car body or frame and the bull gearis detachable into a plurality of separate units of said carbody orV frame, which separate units are, each of the side frame members 35, each of the end frame members 35 yintegrally attached to one diametrical half of the bull gear and to a pair of adjacent I-beams 6l, each ofthe channel pieces 55, and the I-beams 56 and 5l integrally connected by the reinforcing plates 6| and 52. When said reinforcing plates 6I and 62 are detachable, each of the 'I-beams 55 and 56 is a separate unit of the car body or frame. Obviously in the disclosure asmade, the plates 53 are integral with the channel members 65, the plates 5@ are integral with the Lbeams 36 and 6l, the plates 59 and l2 are integral with said I-beams 5l, and the plates 14 are integral with said I-beams 35. The several units constituting the car body or frame and the bull gear of the excavating machine can be transported in knocked down condition and assembled atthe location where the machine is to Yfind use, as will be understood. Of course, the several unitsof the car body or frame and the bull gear can be independently constructed when the machine is being manufactured, to be afterwards assembled together and connected in the manner as set forth. That is to say, while the description as given follows a general sequence to produce thecar body or frame with bull gear, this sequenceV can be altered. For example, the two diametrical halves of the bull gear could be welded to the I-beams 35 and 61 either before or after said I-beams are welded to each other and while disassembled from the side frame members 35. Also, the structure including the I-beams 55 and 5% can be assembled with the I-beams 35 either before or after the side frame members and end frame members 'or I-beams 35 are assembled. And the channels 65 can be assembled into the structure during any preferred stage of its. manufacture. What is intended to be said is, that the units of the car body or framewith bull gear as illustrated and described are not only separate units, but are as well units which can be independently made and, speaking generally, independently assembled together.

The revolvable platform of the excavating machine and its manner of support upon the car body or frame through the instrumentality of the king pin and upon the voperative rail of the bull gear (the lower rail of the excavating machine) through the instrumentality of the upper rails and the rollers o r wheels of the container ring of the machine, will be more clear from Figs. l to 5, 6, 9 and 13. As there disclosed, the revolvable platform includes parallel, spaced apart frame members or I-beams S@ extending the length of said platform, and shorter transversely extending, spaced vapart I-beams 9i, channel members 92 and reinforcing plates 93 connecting said I-beams 95 to each other. The opposite end portions of the members 9|, 92 and 93 are welded to the I-beams 9U, respectively. As shown more clearly in Figs. 4 and 5, the upper and lower flangesV of I-beams 9i and channel members 92 are cut away to terminate flush with the upper and lower ilanges of the I-beams 9?, vand the body portions or Webs of said I-beams 9i and channel vmembers 92 meet the body portions or webs of said I-beams Sil and span the distance between the upper and lower flanges ofthe I- beams 9B. The welding of said members 9i, 92

'and 93 to the I-beams 90 is performed in any suitable manner. The I-beams 9G may include reinforcing webs 94. A floor plate,'or plates, of the revolvable platform consists of a sheet, or sheets, of metal 95 which is welded to the upper the channel members 92 and the reinforcing plates 93. Right and left walkways 96, at the outer sides of the I-beams and flush' with the o floor plate 95, are detachably bolted, as at 91, to the upper, outer flanges of said I-beams 90. A longitudinally extending channel Vmember 98 is welded to the outer portion of each walkway 95, and each walkway structure additionally includes bracing plates 99 which are welded to the walkways 96 and to the channel members 98. The bracing plates 99 are detachably bolted to the I-beams 90, or to reinforcing plates upon said I-beams 90, as denoted at |00. At the rearward end of the platform there is a depending portion I0| which is a continuation of one of the reinforcing plates 93, and right and left bracing plates 99 at this same end of the platform are detachably bolted, as at |90, to said depending portion I9I and the reinforcing plate 93 integral therewith. Thus each walkway structure is detachable from the remainder of the revolvable platform. A vertical reinforcing web |02 is welded to the lower portion of each I-beam 99 and to the depending portion |0I. See Figs. 3 and 4.

The platform of the excavating machine is revolvably mounted by employment of a king pin |03 upon the car body or frame, upper rails |04 upon said platform, and rollers or wheels |05, engaging the operative rail 8| of the bull gear and engaged by said upper rails |04, upon a container ring denoted generally at |06.

r'he king pin |03 is bolted as at 64 and |0I to the upper flanges of the I-beams 55 and 56 and extends vertically upward. Said king pin may additionally be welded to said -beams 55 and 59, as well as to the reinforcing plates 6| and 62. he lower portion of the king pin is of rectilinear conformation, and the upper portion |08 thereof is of reduced, cylindrical shape. Said upper portion |08 of the king pin is directly above the longitudinal and transverse center of` the car body or frame as disclosed.

As will be more clear from Fig. 5, parallel, spaced apart reinforcing plates |09 extend between intermediate I-beams 9| which are adjacent each other, and said reinforcing plates |09 are welded, as at IIi, to said I-beams. A plate I II is welded to the bottom surface of the lower flanges of each of the mentioned I-beams 9|, as at II 2, and divergent bars II3 are welded to each plate III, as at II4. 'I'he bars I|3 are disposed in a horizontal plane and are welded, as at II5, to plates I I6 themselves welded, as at III, in the instance of one set of plates IIE, to a channel member 92, and in the instance of the other set of plates H6, to an I-beam 9| next adjacent an I-beam having a plate I I I. The weldcd-in units each consisting of the plate III, divergent bars |I3 and plates I6 obviously constitute reinforcing members of the platform.

A bearing plate I I 8 is bolted, as at I I9, against the lower surfaces of the plates VI II at location beneath the flanges of the I-beams` 9| having said plates III, the bolts H9 passing through the flanges of the I-beams as well'as through the plates III. Said bearing plate I|8 includes a downwardly extending bearing portion |20 which is situated at the transverse center of the revolvable platform, but at location considerably closer to the front or boom end of the platform than to the rear end thereof, whereby to balance said platform upon its axis against the added weight of the boom, as will be understood. The bearing portion |20 is rotatably mounted upon the cylindrical portion |08 of the king pin, numeral I 2| denoting a bushing in the bearing portion and about the king pin. As will become evident, no means is needed at the location of the king pin and the bearing portion |20 thereon to limit downward movement of said bearing portion upon said king pin, because downward movement of the platform is limited by the engagement of the upper rails |04 with the rollers or wheels |95 and the engagement of said rollers or wheels with the operative rail of the bull gear.l At the upper side of the bearing plate II 8, however, there is disclosed a split collar |22 lying in an annular groove upon the cylindrical portion |08 of the king pin, a Washer |23 being situated between said split collar Vand said bearing plate.

As will be more clear from Figs. l, 4, 5 and 13, a pair of plates, denoted |24 and |25, respectively, extend transversely of the platform in spaced relation to each other, and are suitably welded to the lower surface of said platform; that is, to the lower surfaces of some or all of the members 99, 9|, 92, 93 and 94. An upper rail |94 is weldand and/o-r bolted to each of said plates |24, |25 to extend vertically downward from the platform. Each upper rail is concentric with the axis of the platform, and said upper rails are disposed directly above the operative rail 9| of the bull gear, which operative rail constitutes the lower rail of the excavating machine. could be a single unbroken annular rail, but separate rails arranged diametrically opposite each other and each describing an arc of not more than 90 are suflicient and preferable. The circumference which said upper rails I G4 would describe if continued is exactly equal to and vertically above the circumference described by the bull gear rail 8|.

The container ring |05 consists of inner and outer continuous bands, denoted |26 and I2`I,'re spectively, and the rollers or wheels |05 are freely rotatable on shafts |28 suitably mounted in said inner and outer bands at equally spaced distances apart. Each band |26, |21 can consist of a single strip or piece of metal, or of several strips or pieces of metal connected together in well known or preferred manner. The shafts I 28 for the different rollers or wheels |05 retain the bands |25 and |27 in xed relation to each other. As disclosed more clearly in Fig. 9, eachV shaft |28 is welded, at |29, to the outer band |27, and includes a reduced threaded portion |30 passing through the inner band |29, said reduced portion providing a circumferential shoulder ISI adjacent said inner band |26. A nut |32 upon each threaded portion |30 is turned home against the inner band |26 to force it against Ythe corresponding shoulder |3I. The container ring supports the rollers or wheels |05 in a circumference having diameter equal to that of the circumference described by the bull gear rail 8|, as well as to that of the circumference described by the upper rails |04 continued, and the traveling surface of each roller or wheel I 05v is suitably grooved, as indicated at |33, to it each of said rails 8| and |94. Clearly, when the upper rails |04 are tted to the upper portions of all Yof the rollers or wheels |05 and the lower portions of all of said rollers or wheels are fitted to the operative rail 8| of the bull gear, the platform is mounted for revolvable movement upon the car body or frame about the king pin as an axis, said king pin cooperating in the structure to keep the upper and lower rails properly centered and directly in line with the rollers or Wheels |05.

The upper rails |04 9 Mechanism for revolving the platform in either direction is very clearly disclosed in Figs. 1, 2, 4, 5, 6 and 13. As there disclosed, a bearing plate |34 is bolted, as at |65to the oor plate 65 and to upper flanges upon adjacent I-beam 9| and channel member 62 which are near the forward or boom end of the platform.V Said bearing plate |34 includes a bearing portion |36 extending upwardly therefrom a short distance, and a longer bearing portion |31 extending downwardly through openings in the iioor plate 65 and the plate |25 to position somewhat below the platform. A retainer plate |36 for the bearing portion |31 is welded to the lower surface of the plate |25, and includes an opening |69 in which an annular boss |46 upon the bearing portion |31 is tightly fitted. Thus the bearing portion |31 is very rigidly attached to the lower portion of the platform without the use of bolts or other detachable members which are liable to jar or become loose when the excavating machine in extended use. A vertical shaft |4| is tted to the bearing portions |36 and |31 and extends a short distance beyond the ends of said bearing portions both above and below the platform. A bevel gear |62 is suitabiy fixed to the upper portion of the vertical shaft |l||, and a pinion |63 is suitably xed to the lower portion of said vertical shaft. Said pinion |43 meshes with the gear surface or toothed portion 19 of the bull gear. Numeral |64 denotes a bushing upon the shaft |4| and in the bearing portion |36, said bushing also extending to position between the bevel gear |42 and said bearing portion |36, and |45 indi- Cates a bushing upon said shaft |4| and in the lower part of the bearing portion |31. An electric motor |66 is suitably supported upon the platform. Said motor |66 is set up to drive a pinion |41 in either direction, through the instrumentality of reducing gearing |48. The motor |66 can be a reversible motor, or the mechanism |66 can include devices for reversing the direction of rotation of the pinion |41. Said pinion |61 meshes with the bevel gear |42 to drive said bevel gear. It is to be understood that any other suitable means different from the means illustrated and described can be employed to rotate the bevel gear |62 selectively in either direction. Evidently, when the pinion turned, the bevelgear |62 will also be turned to rotate the shaft |6| and the pinion |63 fixed to said shaft. Rotation of said pinion |63 causes it to ride along the gear surface or toothed portion of the bull gear fixed to the car body or frame, and thus causes the platform to be revolved upon its axis a distance corresponding to the extent of rotation of the shaft |4|, as will be apparent.

The revolvable platform supports a mast, denoted generally at |69, a back brace, indicated generally at |56, said mast and back brace being associated with each other to provide a mast structure for the machine, and a boom, represented generally at |5|. Also, the floor plate of said platform suitably supports front, middle and rear drums, denoted |52, |53 and |56, respectively, which drums are of any ordinary or preferred construction, and an electric motor 215 for the drums. Usual cables |55 and |56 extend from the drums to control the boom and the bucket or` dipper (not shown) of the excavating machine. Said cables can be arranged in any convenient and satisfactory manner, forming no part of the invention, to operate and control the boom and the bucket or dipper. Speaking generally, there are sheaves |51 freely mounted upon the upper portion of the mast structure for cables |55, and

said cables |55 are associated with sheaves |58` and with links |59 having said sheaves |58, said links being suitably pivoted, as at |66, to an upper part of the boom. Also, there are intermediate and lower sheaves, indicated |6| and |62, respectively, freely mounted upon the mast and. upon which cables |56 travel. And the upper end of the boom includes sheaves |63 for,cablesr|56, numeralA |64 representing an ordinary or preferred type of cable guard for said sheaves |63.

The boom |5| is of the novel and improved construction and is mounted upon theplatform. of-

the excavating machine in the novel and improved manner-as now to be described. The structure of the boom and its mounting means is more clearly disclosed in Figs. 1, 2, 4, 5, 13 vto 22 and 23. VAs there shown, said boom is 'constructed inV bottom andtop sections each includ-.

ing longitudinally extending angle pieces, there being an angle piecehaving the apex thereof dening each of the four corners of the boom. The angle pieces of the lboom adjacent to or at the upper surface thereof are denoted |65, |65, and the angle pieces 'adjacent to or at the lower surface of the boom are represented |66, |66. The boom is, speaking generally,1of greater width than thickness, the angle pieces |65, |65 and the angle pieces |66, |66, respectively, being spaced apart at greater distance than is each upper 30 f angle piece |65 and the adjacent lower angle piece |66. v

The bottom section of' the boom includes, in addition to the upper angle pieces |65, |65 and the lower angle pieces-166,'I66ja series of obliquely disposed T-bars |61 at each side of the boom, said T-bars |61 being welded to inner surfaces of adjacent angle pieces`|65, |66, as at |68, with the body portions of the T-barsl extending inwardly as shown. At each side 'ofthe boom, alternatel T-bars |61V are parallel with each other and adjacent T-bars |61 Vare in oblique relation to each other toall but meet, as in Fig. 18, at location where said T-bars are welded'to the angle pieces.

The T-bars |61 at one side of the boom are in staggered relation to the T-bars |61 at the other side of said boom, asshown more clearly in Fig. 14, so that a lattice'effect is the result.

The bottom section-of the boom also includes a series of T-bars at theupper and lower 'sur-v facesof said boom'. Of these T-bars, |69 denotes upper, obliquely disposed T-bars each having its bottom end welded to a lower portion of an angle piece |65, and |10 `represents similar lower, obliquely disposedzT-bars each .having its bottom end welded tol a lower portion of an angle piece |66. The T-bars |69 and |16 are at the outer surfaces of the angle pieces and thev body portions of said. T-bars |69 and |10 extend outwardly from the boom. The upper end of each oblique T-,bar |69 is welded to an upperV plate |1|, and the upper. end Vof each oblique T-bar |16 is Awelded to a'lower plate |12, said plates |11 and |12 being at the transverse center of the boom and attheelevation of the angle pieces |65 and |66, respectively@ An upper T- bar |13 extends transversely of the boom and has its opposite ends welded to the inner surfaces of the angle pieces |65, T-bar |14, directly beneath the T-bar |13, also extends transversely of the boomand has its opposite ends welded to the inner surfaces of the angle pieces |66, |66. The body portions of the T-bars |13 and |14V extend inwardly of the boom. The plate |1| is welded to the T-bar |13,l 75

|65, and a lower and the plate |12 is welded to the T-bar |14. A reinforcing plate |15 at the transverse center of the boom has its opposite ends Welded to the T-bars |13 and |14, respectively. Each of upper, obliquely disposed T-bars. |16 has its bottom end welded to the plate |1| and its top end welded to an angle piece |65, and each of lower, obliquely disposed T-bars |11,has its bottom end welded to the plate |12 and its top end welded to an angle piece |66. The body portions of the T-bars |16 and |11 extend inwardly of the boom., An upper T-bar |18 extends transversely of the boom and has its opposite ends Welded to the inner surfaces of the angle pieces |65, |65, and a similar lower T-bar has its opposite ends welded to the inner surfaces of the angle pieces |66, i 66. The body portions of the T-bar |18 and the similar T-bar directly beneath said T-bar 18 extend inwardly of the boom. The T-bar |18 all but meets the top ends of the T-bars |16 as shown more clearly in Fig. 19, and the lower Tbar which is similar to the T-bar |18 bears this same relation to the top ends of the T-bars |11. A plate |19 is Welded to the upper surface of the flange of the T-bar |18 at the transverse center of the boom, and a similar plate is welded to the lower surface of the ange of therT-bar similar to the T-bar 18 also at the transverse center of the boom. Each of upper, obliquely disposed T-bars has its bottom end welded to the plate |19 and its top end welded to an angle piece |65, and each of lower obliquely disposed T-bars similar to the T-bars |80 has its bottom end welded to a lower plate similar to the plate |19 and directly therebeneath and its top end welded to an angle piece |66. The body portions of the T-bars |80 and the lower T-bars similar thereto extend inwardly of the boom. An upper T-bar |8| extends transversely of the boom and has its opposite ends welded to the inner surfaces ot' the angleV pieces |65, |65, and a similar lower T-bar has its opposite ends welded to the inner surfaces of the angle pieces |66, |66. The body portions of the T-bar 8| and the similar T-bar directly opposite said T-bar |8| extend inwardly of the boom. The T-bar |8| all but meets the top ends of the T-bars |80, and the lower T-bar which is similar to the T-bar |8| bears this same relation to the top ends of the T-bars beneath and similar to the T-bars |80. A plate |82 is Welded to the upper surface of the flange of the T-bar |8| at the transverse center'of the boom, and a similar plate is Welded to the lower surface of the flange of the T-bar similar to the T-bar |8| also at the transverse center of the boom. EachV of upper, obliquely disposed T-bars |83 has its bottom end welded to the plate |82 and its top end welded to an angle piece |65, and each of lower obliquely disposed T-bars similar to the T-bars |83 has its bottom end welded to a lower plate similar to the plate |82 and directly therebeneath and its top end welded to an angle piece |68. The body portions of the T-bars |83 and the lower T-bars similar thereto extend inwardly of the boom. An upper T-bar |84 extends transversely of the boom and has its opposite ends welded to the inner surfaces of the angle pieces |65, |65, and a similar lower T-bar has its opposite ends welded to the inner surfaces of the angle pieces |66, |66. The Vbody portions of the T-bar |84 and the similar T-bar directly beneath said T-bar |84 extend inwardly of the boom. The T-bar |84 all but meets the top ends of the T-bars |83, and the lower T-bar which is similar to the T-bar |84 bears this same relation to the top ends of the T-bars beneath and similar to the T-bars |83. A lseries of obliquely disposed T- bars |85 at the upper and lower surfaces of the boom are welded to inner surfaces of adjacent angle pieces |65, |65 and |66, |68, respectively, with the body portions of said T-bars |85 extending inwardly o the boom. At each of the upper and lower surfaces of the boom, alternate T-bars |85 are parallel with each other and adjacent T-bars |85 are in oblique relation to each other to all but meet, as in Fig. 19, where said T-bars are welded to the angle pieces. The T-bars |85 opposite each other, at the upper and lower surfaces of the boom, are in staggered relation, as shown very clearly in said Fig. 19 so that a lattice effect is the result.

The bottom section of the boom is joined tothe top section thereof at location just above the T- bars |61 and 85, said bottom section permanently supporting means for making the connection between the sections. At the location of the joint between said sections, the bottom section is reinforced by eight plates, including uppervplates |86, |86 attached to the horizontal arms of the angle pieces |65, |65, upper plates |81, |81 attached to the Vertical'arms of said angle pieces |65, |65, lower plates |88, |88 attached to the horizontal arms of tlie'angle pieces |66, |66, and lower plates |89, |89 attached to the vertical arms of said angle pieces |66, |66.V 'Ihe'plates |86, |81, |88 and |89 are on the outer surfaces of the arms of the angle pieces and terminate approximately ilush with the apices of said angle pieces. As shown, said plates and angle pieces are secured together by rivets |98, but could be Welded to each other. Each plate |86, |81, |88 and |89 includes portions thereof extending upwardly beyond the top of, and inwardly beyond the inner edge, the angle piece arm carrying said plate. An upper T-bar |9|, arranged transversely of the boom, has the opposite ends of its flanges welded to the inner surfaces of the inwardly extending portions of the plates |86, |86, with the body portion of said T-bar |9| extendingr inwardly of the boom. A lowerr T-bar |92, also arranged transversely of the boom and disposed opposite said T-bar |9|, has the opposite ends of its anges welded to the inner surfaces of the inwardly extending portions of the plates |88, |88, with the body portion of said T-bar |92 extending inwardly of the boom. And each of side T-bars |93, in the plane of the T-bars |9| and |92, has the opposite ends of its ilanges Welded to the inner surfaces of the inwardly extending portions of adjacent plates |81, |89, with the body portions of said T-bars |93 extending inwardly of the boom. Bracing plates |94, one adjacent each corner of the boom, are welded to the opposite ends of the body portionsof the T-bars |9|, |98 and |92, |93, respectively, and a T-bar |95 extends between opposite bracing plates |94 and' has its ends Welded thereto.

The lower parts of the angle pieces |65, |65, |66 and |66 of the top section of the boom are provided with bolt holes |96 which are adapted to aline with bolt holes |91 in the upward extensions of the plates |86, |81, |88 and |89, Bolts |98 in said bolt holes |96 and |91 detachably connect the bottom and top sections of the boom together with corresponding angle pieces of the different boom sections in alinement, as is apparent. ie lower part of the top section of the boom includes an oblique T-bar |99 at one side of said boom welded at its upper end to an angie piece |65 and 4having bolt holes 288 at its lower end adapted to aline with bolt holes 26| in a plate |89. Bolts 262 connect said T-bar |516 with said plate |89. An oblique T-bar 263 at the other side of the boom, opposite the T- bar |99, is weldedat its upper end to an angle piece |66 and has bolt holes 204 at its lower end adapted to aline with bolt holes 265 in a plate |8ll. Bolts 266 connect said T-bar 263 with said plate |871. An oblique T-bar 267 at the upper surface of the lower part of the top section ofv the boom is welded at its upper end to an angle piece |65 and bolted at 2126 to a plate |86. An oblique T-bar 269 at the lower surface of the lower part of the top section of the boom, opposite the T-bar 261, is welded at its upper end to an angle piece |66 and bolted at 2|6 to a plate |88. The body portions of the T-bars |99, 263, 25? and 266 extend inwardly of the booin, and the flanges of said T-bars are cut away at the locations where the T-bars are bolted.

Directly above the T-bars |69 and 263 the top section of the boom includes an additional series of obliqucly disposed T-bars |6'l at each side of said boom, which additional T-bars |61 are welded into the boom structure and have the same relative arrangement to the angle pieces and to each other as hereinbefore described.

Directly above the T-bars 261 and 266 the top section of the boom includes a series of T-bars at the'upper and lower surfaces of said boom. Of these T-bars, 2| denotes an upper T- bar extending transversely of the boom and having its opposite ends welded to the inner `surfaces of the angle pieces |65, |65. A lower T-bar, similar to the T-bar 2|| and directly opposite said T- bar 2| has its opposite ends welded to the inner surfaces of the angle pieces |66, |66. The body portions of the T-bar 2| and the similar, directly opposite T-bar extend inwardly of the boom. Directly above the T-bar 2| and the lower,.similar T-baropposite said T-bar 2| I, the top section of the boom includes a series of obliquely disposed T-bars 2|2 at the upper and lower surfaces of said boom. Upper T-bars 2|2 are welded to the inner surfaces of the angle pieces |65, |65, and lower T-bars 2 l2 are welded to the inner surfaces of the angle pieces |66, |66, with the body portions of all of said T-bars 2 l2 extending inwardly of the boom. At each of the upper and lower surfaces of the boom, alternate T-bars 2|2 are parallel with each other and adjacent T-bars 2 l2 are in oblique relation to each other to all but meet, as shown in Fig. 20, at location where said T-bars are welded to the angle pieces. The T- bars 2|2` at the upper surface of the boom are in staggered relation to the T-bars 2|2 at theV lower surface of said boom,V so that a lattice effect is the result.

Reinforcing plates 2|3, one at each side of the upper part of the top section of the boom, are welded to the outer surfaces of upper and lower angle pieces |65, |66 and |65, |66, respectively, as shown more clearly in Figs. 14 and 20. The outer end of each plate 2 |3 terminates about flush with the upper or outer ends of the angler pieces |65, |65, |66, |66. Small plates 2|5 are welded to the outer surfaces of the plates 2|3 at location adjacent to the upper or outer end of the boom, and a shaft 2|6 for the sheaves |63 is suitably mounted in each of the opposite plates 2|3 and 2|5. Small plates 2|'l are welded to the outer surfaces of the plates 2|3 at location slightly inwardly from the plates 2|5, and support, together with said plates 2|3, the pins or pivots |653 which attach the links |59 to the boom. A reinforcing plate 2|8 extends transversely of the boom at the inner sides of the plates 2li and adjacent to the T-bars 2|2. Said plate 2|8 is welded to the inner surfaces of the angle pieces.

Reinforcing plates 2|9, one Vat the upper surface and one at the lower surface of the boom, extend transversely of said boom and are welded to the outer surfaces of arms of the angle pieces |65, |65 and |66, |66, respectively. The outer extremities of the plates 2 9 terminate just below the sheaves |63, and the inner end portions of said plates 2 |9 extend to position along the boom below the elevation of one or more T-bars 2|2 and additional T-bars |61.

While the illustration as made in the drawings and the description as given are of a boom consistingV of two sections, one a lower section and the other an upper section, attention is called to the fact that the boom can be constructed as a single section extending the length of said boom, or can consist of more than two sections. In the latter event, additional sections could be connected into the boom structure in the manner as hereinbefore fully set forth, or in any other suitable and preferred manner.

The inner or lower end portion yof the bottom section of the boom carries supporting bearing members 226, one at each side of the boom, for said boom. Longitudinally extending reinforcing plates 22|, one at each side of the boom, are welded to the'outer surfaces` of the angle pieces |65, |66 and |65, |66, respectively, and each'bearing member 226 includes an integral web or attachment portion 222 which is riveted, as at 223, to the lower or bottom parts of the adjacent plate 22| and the adjacent angle pieces |65, |66. The

Vwebs or attachment portions 222 are at the inner sides of the angle pieces, and each web or attachment portion'222 has relation to its bearing member 226 and to the adjacent angle pieces |65, |66 situating the bearing members 226 at the midthickness of the boom. Each bearing member 226 is desirably in a plane including the angle pieces |65, |66 at the corresponding side of the boom. Numeral 224i denotes openings providing opposed bearing surfaces of each bearing member 22|), all of which bearing surfaces 22d are in a line extending transversely of the boom at the midthickness thereof.

At the forward or boom end of the platform Y of the excavating machine, each longitudinal beam 69 includes elongated slots 225 in the upper flanges thereof which open to the forward or boom ends of said I-beams 66 and extend rearwardly at the opposite sides of the body portions of said l-beams, as shown very clearly in Fig. 28. A plate 226 is welded to each of the opposite surfaces of the body portion of each I-beam 66 and extends upwardly through an elongated slot 226, numeral 22'.' denoting portions of the plates 226 extending above the I-beams 9E). A smaller plate 228 is positioned between the portions 227 of the plates 226 on each I-beam 96 and is welded to said portions 227. The lower end of each plate 223 is contiguous with the corresponding I-bearn and may also be welded to said I-beam. Each structure as described, at either side of the forward or boom end of the platform and including the plates 22@ with upward extensions 227 and the plates 223 between said extensions 227, constitutes means cooperating to support both the mast M2 and the boom I5! upon the platform. That is to say, the Velements 227, 228, 227, which are integrally connected and are integral with the I-beams 93, provide spaced apart bearing blocks, denoted 22S, upon which both the mast M3 and the boom 15! are mounted. At the forward or boom end of the platform, a transverse plate 273 is welded to the forward end of each I-beam 3@ and to each bearing block 223. The plates 275 support bracing plates 99.

Each bearing block 223 includes an opening 23E at the forward or boom end thereof, said openings 23B lying in a line extending transversely of the platform. The boom is mounted upon the bearing blocks 223 by means of pins 23E, one for each bearing block on the platform and each bearing member on the boom, which pins are suitably retained in the openings 224 of the bearing members 22D and in the openings 233 of the bearing blocks. Each bearing block 229 is between opposed bearing surfaces of a bearing member 223, and washers 232 are situated between the bearing blocks and the adjacent bearing surfaces of the bearing members.

The mast Idil and the back brace |50 are of the novel and improved construction and are mounted upon the platform of the excavating machine and connected with each other in the novel and improved manner as now to be described. The structure of the mast and ofthe back brace and their mounting means, and of the means connecting the upper portions of said mast and back brace with each other, is plainly disclosed in Figs. l, 2, 4, 5, 13, 23 to 27 and 29. As there shown, said mast includes longitudinally extending channel pieces 233 having their flanges projecting outwardly of the mast. Said channel pieces 233 are at the opposite sides of the mast and converge upwardly, and a plurality of strengthening and reinforcing elements interconnect the channel pieces. Said mast includes, in addition to the channel pieces 233, plates 234 welded to the opposite upper flanges of the channel pieces at the bottom of said flanges, and plates 235 welded to the opposite lower flanges of the channel pieces 233 at the bottoms of said flanges. The plates 234, 234 and 235, 235, respectively, extend inwardly of the mast toward each other. Upper and lower transverse channel bars 255 have their opposite end portions welded to the outer surfaces of the plates 234, 234 and 235, 235, respectively. The mast also includes plates 236, above the plates 234 and spa-ced therefrom, welded to the opposite upper flanges of the channel pieces, and plates 237, above the plates 235 and opposite the plates 236, welded to the opposite lower flanges of the channel pieces. spectively, likewise extend inwardly of the mast toward each other. Oppositely disposed channel pieces are situated between the channel pieces 233, in spaced relation to each other and to said channel pieces 233, at the elevation of the plates 234, 235, 235 and 237, and have their flanges projecting outwardly. The upper parts of the body portions of the channel pieces 238 are parallel, and lower parts of said channel pieces 238 diverge downwardly and terminate in close proximity to The plates 2325, 233 and 237, 237, re-V the channel pieces 233. All of the channel pieces 233, 233, 238 and 233 are in a single plane passing longitudinally through the mast. The opposite anges of the channel pieces 238 are welded to all of the plates 234, 235, 235 and 237. Said channel pieces 238 include suitable bearings for the shafts 233 of the sheaves itil and I62.

A- transverse channel bar 240 at the elevation of the plates 233 and 237 has its opposite end portions welded to the body portions of the channel pieces 233, to the top ends of the channel pieces 238, and to the inner surfaces of all of the plates 235 and 237. A series of obliquely disposed T-bars 24! at the upper and lower surfaces of the mast are welded to opposite flanges of the channel pieces 233 at location directly above the channel bar 243, with the body portions of said T-bars 24! extending outwardly of the mast.V At each of the upper and lower surfaces of the mast, alternate T-bars 24| are parallel with each other and adjacent T-bars 24! are in oblique relation to each other to all but meet, as shown in Fig. 26, where said T- bars are welded to the flanges of the channel pieces. The T-bars 24! opposite each other, at the upp-er and lower surfaces of the mast, are in staggered relation, as shown quite plainly in said Fig. 26, so that a lattice effect is the result.

Reinforcing plates 242, one at the upper and one at the lower side of the mast near the top thereof and directly above the T-bars 24|, are welded to the opposite flanges of the channel pieces 233. Said plates 242 are cut away at 243 to clear the sheaves |57. A shaft 244 for said sheaves l57 is mounted in suitable bearings in the channel pieces 233 at location above and adjacent to the plates 242 and not far from the upper end of the mast. A reinforcing channel bar 245 extends transversely of the top end of the mast and is welded to the ends of the channel pieces 233. Spaced apart, vertical plates 246 are welded to the inner surfaces of the body portions of the channel pieces 233, and extend downwardly toward the back brace !50, as will be more clear from Figs. l, 23 and 27. Each plate 24S is welded to two smaller plates 247, said plates 247 in each instance being at the lower edge of and at the opposite sides of the plate 246 by which they are supported. Said plates 247, 243, 247 provide means upon the mast for attaching said mast and the back brace to each other in a manner which will be set forth. Y The downwardly divergent portions of the Vchannel pieces 233 merge at their lower ends into short bottom parts 243 of said channel pieces 233, including a bottom part 24B having its body portion arranged adjacent to and parallel with the body portion of the bottom part of each channel piece 233. A small plate 249 is welded to the inner surface of the body portion of each bottom part`248, and a small plate 253 is welded to the outer surface of the body portion of the bottom part of each chanv are in a line extending transversely of the mast, as well as in the plane of the mast.

Each bearing block 229, including an opening 235 for' mounting the boom, also includes anV opposed mounting surfaces of a bearing or supporting memberV 25|.

The back brace |55 includes longitudinally ex' tending I-beams 255 at the opposite sides of said back brace. Lower portions 251 of said I-beams 255 are parallel, and upper portions 258 of the I-beains converge upwardly, numeral 259. denoting a bend line of each I-beam 255 where the lower and upper portions 251 and 258 thereof meet. Strengthening and reinforcing elements interconnect the I-beams 255. Said back brace includes, in addition to the I-beams 255, a transverse I-beam 255 extending between said `I- beams 255v at the location of the bends 259, said I-beam 255 having its opposite end yportions welded to the I-beams 255. The brace also includes plates 25| welded to the opposite upper flanges of the I-beams 255'and 255, and plates 252 welded to the opposite lower flanges of said n 255. The upper end of the body portion of each I-beam 255 supports two small plates 264, said plates 254 in each instance being at the opposite sides of said body portion of the I-bearn 255 by which they are supported and terminating flush with the upper end of said I-beam, as will be more clear from Fig. 25. The plates 254 are welded to the I-beams. welded to the outer surfaces of each plate 254, and said plates 255 in each instance include spaced apart portions 255 extending vertically upward from attach the back brace and the mast to each other, Yeach set of plates 241, 245, 241 upon the mast is positioned between a set of spaced apart portions 255 upon' the back brace, and a pin 251 is inserted and fastened in openings 258 through said sets of plates and said sets of spaced apart portions.

The platform of the excavating machine includes a transverse I-beam 259 welded to the lower surfaces of the I-beams 95 and extending beyond the outer sides of said I-beams 95, as shown more clearly in Figs. 1, 4 and 23. The lower portions of the parallel parts 251 of the I-bearns 255 extend downwardly through openings 215 in the walkways 95. See Figs. 2 and 23. The lower end of the body portion of each I-beam 255 supports two small plates 21|, said plates 21| in each instance being at the opposite sides of said body portion of the I-beam by which supported and terminating ush with the lower end of said I- beam, as will be more clear from Fig. 24. 'Ihe flanges of each I-beam 255 are cut away at the elevation of said plates 21|, and said plates are welded to said I-beams. Spaced apart, vertical A larger plate 255 `is the corresponding I-beam 255. To

plates 212 are fitted upon and welded to the opposite end portions of the transverse I-beam 259, asshown veryclearly in Figs.r 1 and 23.` Said vertical plates 212 extend upwardly above the I#4 beams 259. To attach the back brace tothe platform, the lower end of each I-beam 255 with plates 21| welded thereto is positioned between a set of spaced apart plates 212 upon the pI-beam 269, and each of pins 213,' one for each connection to be made, is inserted and fastenedin openings 214 through each set of plates 212 and through each I-beam 255 and ther plates'21l` thereon. The connections between the I-beams 255 and the platform are in a horizontal line extending transversely of the platform. f

Both the mast |45 and the back brace |55 lie in a vertical plane passed longitudinally through the platform. Said mast slants downwardly at desired angle from rear toward front of the plat form, and said back brace slants downwardly at` desired angle from front toward rear of said platform, to provide a mast structure the upper fpor` tions of which are connected together at location above and between the locations where said mast and said back brace are mounted upon the platform, as is customary.

What is claimed is:

1. In an excavating machine, a car body, a platform, means supporting said platform upon said car body, and means for revolving said plat'- form upon its support, said last mentioned means comprising a gear surface upon said car body, a pinion engaging said gear surface, a 4shaft carrying said pinion, devices for rotating said shaft, a bearing for said shaft, a plate integral with said bearing and bolted to an upper portionv of said platform, and a plate Welded to allower` portion of said platform, said bearing extending downwardly through an opening in said last mentioned plate and being tightly flttedto said open? ing, and said shaft projecting beyond the opposite ends of said bearing. c

2. In an excavating machine, prising a plurality of part-circle elements adapted to be detachably connected, anda member consisting of separable parts for supporting said bull gear, each of said part-circle elements cona bull gear comsisting of a part-circle, upstanding portion, a sec-` ond part-circle, upstanding portion havinga hor. l

izontally disposed lowerfrail surface serving as a support in said excavating machine, said partcircle portions being in Yconcentric relation, a gear surface uponv one `of said part-.circle port ionsl and n a connecting web between said part-circle por` arable parts of said supporting member.

3. An excavating machine comprising a car body, a platform upon said car body, a member revolvably supporting said platform upon said car body, an upstanding lower rail portion upon said car body and carrying an upstanding portion having a gear surface, said lower rail portion being concentric with said supporting member and said gear surface, a web integrally connecting the bases of said upstanding lower rail portion and said upstanding portion having said gear surface, said web resting upon and being secured to said car body, an upper rail portion upon said platform above said lower rail portion, a roller member engaging said lower rail portion and supporting said upper rail portion, and means engaging said gear surface for revolving said platform.

4. In an excavating machine, a car body, and

tion, and the Web portion including a bottom sur-V face supported upon-said car body.

5. In an excavating machine, a car body, and a bull gear supported upon an upper surface of said car body, said bull gear being constituted as an integral structure adapted to be fastened down upon said car body and comprising a web portion, an operative rail at one side of said web n portion and integral therewith and extending upwardly from the web portion and the car body, and a portion at the opposite side of said web portion and integral therewith and providing a gear surface in spaced relation to said operative rail.

6.*In an excavating machine, a knock-down car body structure comprising longitudinally extending side frame members, transversely extending end frame members, means for detachably ccnnecting meeting portions of said side frame mem- ;bers and said end frame members to each other,`

and a bull gear .consisting of a plurality of sepa-V rate part-circle members each constituted as an integral structure independently secured to a framemernber, each part-circle member compris-l ing a connecting web, a part-circle element at oneside of said connecting web and extending upwardly therefrom and providing part of an operative rail for said excavating machine, and a second part-circle element at the opposite side o f said connecting webl and providing a gear surface in spaced and concentric relation'to said operative rail. f

7. Inan excavating machine, the combination with a knock-down car body structure comprisingV longitudinally extending side Vframe members, transversely extending end frame members, and means for detachably connecting meeting portions of said side frame members and said end frame members to each other, of a bull gear consisting of a plurality ofvseparate partecircle mem.- bers each constituted as an integral structure separately and independently secured to a frame member, each part-circle member comprising a connecting web resting upon a frame member, a

part-circleelement integral with one side of said connecting web and extending upwardly above the plane of the web and providing part of an operative rail for said excavating machine, and a second part-circle element integral with the opposite side of said connecting web and providing a gear surface in spaced and concentric relation to saidoperative rail.

8. In an excavating machine, a'bull gear comprising a plurality of part-circle members adapted to be detachably connected, and a member consisting of separable parts for supporting said bull gear, each of said part-circle members consisting of a part-circle upstanding element, a second partcircle upstanding element having an operative rail surface serving as a support in said excavating machine, said part-circle elements being in concentric relation, a gear surface upon one of said part-circle elements,V and a connecting web between and integral with said part-circle elements and below said operative rail, the connecting web of each part-circle member being permanently and independently secured to one of the separableparts of said supporting member.

9. In an excavating machine, a bull gear comprising a plurality of independent part-circle members, and a member consisting of separable parts for supporting said bull gear, each of said part-circle members consisting of a part-circle element, a second part-circle element having an operative rail surface servingas a support in said excavating machine, said part-circle elements being in concentric relation, a gear surface upon one of said part-circle elements, and a connecting web between and integral with said part-circle elements, the connecting web of each part-circle member Y being permanently and independently secured to one of the separable parts of said Asupporting member.

Y l0. In an excavating machine, a bull gear comprising a pluralityV of independent part-circle members, and a member consisting of separable parts for supporting said bull gear, each of said part-circle members consisting of a part-circle element, aV second part-circle element having an operative rail surface serving as a support in said excavating machine, said part-circle elements being in. concentric relation, a. gear surface upon one of said partcircle elements, and a connecting web betweenV and integral with said part-circ1e elements, each ofA said part-.circle members being permanently and independently secured to one of the separable parts of said supporting member.

ROLF E. LJ UNGKULL. 

